Hi Joerg,
thanks for your quick reply.
Thus wrote Joerg Mayer (jmayer@xxxxxxxxx):
> Take a look at packet-extreme.c and search for hf_edp_checksum_good
> (similar code can be found in other dissectors). The core point is
> setting the item to PROTO_ITEM_SET_GENERATED. Does this do what you
> want?
The "checksum ok?" item is not directly taken from the tvb but it is
still linked to a part of the tvb, the checksum itself.
In my case, I don't have any tvb but a value in a guint32. I've had
another look and guess that
it = proto_tree_add_uint_format(tree, hf_myproto_myfilter,
NULL, 0, 0, <value from the guint32>, ...);
does what I want. My understanding is that I can pass tvb==NULL if
length==0 as well. The value is assigned to the hf without any reference
to a tvb. I'd then set PROTO_ITEM_SET_GENERATED(it) on the result.
> I haven't verfied this, but as pinfo->fd->num ist the frame number it seems
> to be extremely likely to be safe :-)
ok, null checks removed
> I assume you mean se_alloc(). epan/emem.c internally uses g_malloc unless
> some special steps are taken (debugging).
ok, understood
Best regards,
Martin